Abstract:
This award supports a project to use two spectrofluorimeters - one with a 224-nm laser to excite protein fluorescence and non-protein aerosol and dust fluorescence, and the other with a 404-nm laser to excite F420 fluorescence (a proxy for methanogens) and chlorophyll fluorescence (a proxy for aerobes) - in order to scan ice core sections at NICL and look for abrupt climate changes, volcanic ash, ... microbial concentrations, and correlations among them. With the fluorimeters we will scan selected lengths of ice cores from GISP2, WAIS Divide, Siple Dome, and Vostok at NICL. Among the biomolecules the fluorimeters can identify will be chlorophyll, which will provide the first map of aerobic microbes in ice, F420, which will provide the first map of methanogens in ice, and organic and mineral aerosols in ice. With the ability to map fluorescence over hundreds of meters in depth with 300 micrometer sampling frequency, we will search for abrupt variations in arrival rate of Aeolian microbes and other aerosols, and we will find out whether spike-like anomalies in nitrous oxide and methane are due to in-situ microbial metabolism. We will collaborate with others in relating results from WAIS Divide and NICL ice cores to broader topics in climatology, volcanology, and microbial ecology. We will continue to give broad training to undergraduate and graduate students, to attract underrepresented minorities to science, engineering, and math, and to educate the press and college teachers.

Description:
WAIS Divide is a United States deep ice coring project in West Antarctica funded by the National Science Foundation (NSF) and is the second component to the larger WAISCORES initiative. The purpose of the WAIS Divide project is to collect a deep ice core from the flow divide in central West Antarctica in order to develop a unique series of interrelated climate, ice dynamics, and biologic records focused on understanding interactions among global earth systems.